2016 Audi A6 P0087

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HillVS
Newbie
Posts: 7
Joined: Tue May 15, 2018 2:41 pm

2016 Audi A6 P0087

Post by HillVS »

Hi,

I have a Audi A6 CHNA engine code.
It’s been with another garage and had the fuel filter and rail pressure sensor done.
The car flags the code when you ask for more throttle.
Rail pressure is whilst driving is consistently 200bar under desired. Idle it’s spot on. Supply to the pressure sensor is fine and doesn’t drop out the signal looks good again doesn’t drop out.
I believe this car has a inlet metering solenoid and want to test that but can this be done with a amp clamp to see if the valve is operating when being told to?
Thanks in advance
Mike.

JJW
Newbie
Posts: 5
Joined: Tue Mar 20, 2018 8:41 pm

Re: 2016 Audi A6 P0087

Post by JJW »

Hi Mike, unfortunately it is pretty much always the case that these low pressure issues are caused by mechanical damage on the pump sending swarf into other components (normally caused by a historic mis-fuel or years of poor quality fuel), usually starting with the pressure regulating valve on the end of the rail (it only takes a microscopic shard of swarf to keep this open slightly and prevent pressure reaching specification under load). Remove the valve from the HP pump carefully and check for swarf. Do not remove the valve from the rail unless you intend to replace it. There are checks that can be done with the PicoScope to check the HP system overall. Check Frank Masseys videos on youtube for DRV testing.

HillVS
Newbie
Posts: 7
Joined: Tue May 15, 2018 2:41 pm

Re: 2016 Audi A6 P0087 FIXED

Post by HillVS »

Hi sorry I didn’t see your reply,
I did check the DVR for swarf and as it was a new pump fitted by Audi but all was clean, I carried out the frank massy dvr test and that was an experience I can say! The volts shot to 4.5v then dropped almost immediately, so proved I had a major hp system leak. I did a idle flow test on all injectors and it was higher than the expected value. Sent the injectors off for testing and all failed under load 1800 bar! So new injectors and all is well with the car. Thankyou for your time.

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